Float switch for swimming pools



July 26, 1966 G. c. MEYER FLOAT SWITCH FOR SWIMMING POOLS Filed March l2, 1965 Hl I qi man fa/wf 6. MEYER' ATTORNEYS.

United States Patent O 3,263,041 FLOAT SWITCH FOR SWIMMING POOLS George C. Meyer, 5037 Corvair St., North Highland, Calif. Filed Mar. 12, 1965, Ser. No. 439,189 Claims. (Cl. 200-84) This invention relates to an improved oat supported signalling device for swimming pools, and in particular to an improved and simpliiied float with electrical connections thereon for the purpose of actuating an alarm.

Due to present improvements in water purification and in the interest of cutting installation costs, the installation of unfenced swimming pools on residential properties is becoming increasingly popular with property owners who do not want to go to a crowded beach for a swim. However, installations -of such pools have the attendant problems of safeguarding small neighborhood children from being attracted to and accidently falling into such pool when no attendant is present, thereby subjecting the owner of the pool to legal liability.

The instant invention simplifies the solution of the above problem simply and inexpensively by providing a reliable alarm actuated by wave action should a small child have the mishap of falling into an unattended swimming pool.

A primary object of the present invention is 'therefore to provide an improved type of alarm for a swimming ool. p Another object of the instant invention is to provide an improved float-type signaling means which precludes the possibility of transmitting an electrical shock to persons in the swimming pool.

Another object of the invention is Ito provide an alarm means for swimming pools which is simple to use, economical to make and inexpensive to maintain.

Another object of the invention is to provide a unitary float means which may be formed of inexpensive light weight water-resistant material, such as plastic, Styrofoam or the like.

It is another object of the instant invention to provide a float means which immediately senses wave motion caused by a child or other large object falling into the Water of the pool, causing prompt actuation of the alarm.

Other objects and advantages of this invention reside in the combinations of elements, arrangements of parts, and features of construction and operation, all as will be more fully pointed out hereafter and disclosed in the accompanying drawings wherein there is shown a preferred embodiment of this invention.

In the drawings:

FIGURE l is a side elevational view of an alarm for swimming pools embodying one form of the instant invention;

FIGURE 2 is a plan view of the device as shown in FIGURE l;

FIGURE 3 is a sectional view taken along line 3 3 of FIGURE 2 as viewed in the direction indicated by the arrows;

FIGURE 4 is a showing of a mercury switch element utilized to close an electrical circuit in the float means shown in FIGURE 2;

FIGURE 5 is a plan view of a modiiied form of a float means embodying the instant invention;

FIGURE 6 is a sectional view taken along line 6-6 of FIGURE 5 as viewed in the direction indicated by the arrows; and

FIGURE 7 is a showing of one form of alarm that may be connected to the electrical circuit of a iloat means embodying the instant invention.

Referring now in detail to the accompanying drawings and more speciically to FIGURES 1 to 3, inclusive, a

Patented July 26, 1966 ice iioat means is shown generally at 10, lying in a body of water 11. The oat means v10 comprises a cylindrical body shown generally at 12 which may be constructed of an upper body portion 14 and a lower body portion 16 or which may be formed or molded as a unitary piece from a lightweight, strong, water-resistant substance such as plastic, Styrofoam or the like.

The upper body portion 14 contains a series of indentations 18 symmetrically spaced about the axis 19 of cylindrical body 12. Each of the indentations 18 comprises a lower surface 20 sloping outwardly from the axis 19 and contains a mercury level switch 22 having its longitudinal .axis pointed toward axis 19 and extending along a radius of cylindrical body 12. Mercury level switch 22 has a hollow interior volumey 23 into which a pair of wires 24, 26 extend. Also provided in the interior 23 is a mercury bubble 25 of a volume substantially less than the total volume of the interior 23. As is apparent from FIGURE 4, the mercury bubble 25 normally lies at one end of the interior 23 away from the ends of wires 24, 26. As will be evident, a tilting of the mercury level switch 22 completes an electrical contact between the ends of wires 24, 26, for a purpose to be hereinafter described.

The undersurface of lower body portion 16 presents a series of truncated spherical indentations 27 which act to entrap air underneath the float means 10 increasing the buoyancy thereof and lessening the weight, thus providing a float that quickly and accurately responds to wave motions to actuate an alarm. As is apparent from FIGURE 2, the indentations 27 are symmetrically arranged with the axis 19`of the cylindrical body 12.

Insulated wires 24, 26 lead from each mercury switch .22 disposed in one of the three indentations 18 to a central connection 28 coaxial with axis 19 of body 12. Wires 24, 26 make continuous electrical connection with an outlet wire 30 leading from beneath the float 10 which in turn makes connection with an alarm device shown generally at 32 in FIGURE 7. Since the ou-tletwire '30 is connected to cylindrical body 12 coaxial with the axis 19 thereof, the weight of the wire 30 will not impair the sensitivity of the ioat means 10 with respect Ito induced wave motion.

The alarm 32 comprises a pair of lead wires 34, 36 extending from outlet wire 30 to a pair of terminals 38, 40 of a battery 42. Another pair of wires 44, 46 connects the battery 42 to an audible alarm 48 which has a conventional gong 50 and movable clapper 52 thereon.

Since the ends of wires 24, 26 do not normally close the circuit including wires 24, 26, 30 and alarm device 32, the circuit is normally not energized, thus conveniently allowing the use of a battery-powered alarm although a continuous circuit alarm may be utilized.

As is apparent from the previous description, the iioat means 10 lies relatively motionless when the body of water 11 is quiescent. Since swimming pools are normally exposed to naturally occurring air currents, a relatively constant wave pattern is set up on the water surface 11. In order to accommodate this wave pattern without actuating the alarm device 32, the mercury level switch 22 is constructed of such a length that the mercury bubble 25 will not contact the ends of wires 24, 26 when the iioat means 10 is subject to a normally occurring Wave pattern. When a child or other sizable body falls into the water of the swimming pool, an abnormally large wave pattern will be established. As the float means 10 is aifected by this wave pattern, the cylindrical body 12 will be tilted thereby causing the mercury bubble 25 to contact the ends of wires 24, 26, thereby closing the electrical circuit and sounding the alarm 3.2. i

D regardless of the direction from which the wave pattern emanates. Likewise, the symmetrical positioning of the mercury level switches 22 will repeatedly close the electrical circuit to the alarm 32 during the life of the abnormal wave pattern propagated by the falling of a child into the water.

Referring now to FIGURES and 6, another float means shown generally at 54 is provided which embodies the instant inventive concept. Float means S4 comprises Ia cylindrical body portion 56 which is preferably composed of an upper body portion 58 and a lower body portion 6G secured together, or which may be formed or molded as an integral piece in the same manner as the embodiment of FIGURES 1 and 2. Upper body portion 58 forms three symmetrically arranged indentations 62 similar to those disclosed previously. The lower body portion 60 comprises .a propeller-shape structure 63 having blades 64 thereon arranged symmetrically with respect to axis 66 of body 56. The three blades 64 form a series of recessed portions 68 on the underside of lower body portion 60. These recessed portions 68 serve the same purpose and act in substantially the same manner as the truncated spherical indentations 27 of the embodiment shown in FIGURE 2. Float means 54 is equipped with a series of mercury level switches and an electrical circuit in the same manner as previously discussed, and operation of float means 54 is substantially identical with the operation of float means 10.

From the foregoing it will be seen that there is provided an improved alarm for swimming pools which accomplishes all of the objects of this invention and others, including many advantages of practical utility and commercial importance.

As many embodiments may be made within this inventive concept, and as many modifications may be made in the embodiment hereinbefore shown and described, it is to be understood that all matter herein is to be interpreted merely as illustrative and not in a limiting sense.

I claim:

1. In an alarm for swimming pools, a oat comprising a substantially cylindrical body having a central axis and a radius, said body having an upper surface providing at least one surface means sloping from said axis toward the periphery of said body adapted to support an alarm actuated switch means, a lower surface, said lower surface including means for entrapping air beneath said oat, said last mentioned means including symmetrically downwardly extending portions forming a series of open cut-out areas.

2. The device of claim 1 wherein said downwardly extending portions form three truncated spherical indentations symmetrically .arranged with respect to said axis.

3. The device of claim 1 wherein said downwardly extending portions form a propeller-shaped structure having three blades thereon arranged symmetrically with respect to said axis.

4. The device of claim 1 wherein said switch means includes a mercury level switch having a longitudinal axis xedly secured to said sloping surface, said switch being comprised of an outer shell defining .a closed interior recess, a pair of electrical contacts extending through said outer shell and a mercury bubble in said recess, said switch being aligned longitudinally with said body radius, said electrical contacts being disposed nearest said axis.

5. The device of claim 1 wherein said body forms three sloping surfaces symmetrically arranged with respect to said axis, each of said surfaces having a mercury level switch having a longitudinal axis tixedly secured thereto, each of said mercury level switches being comprised of an outer shell forming an interior volume, a pair of electrical contacts extending through said outer shell and a mercury bubble within said outer shell, said switch being positioned with the longitudinal axis thereof extending along said body radius with said electrical contacts disposed nearest said axis.

References Cited by the Examiner UNITED STATES PATENTS 2,646,067 7/1953 Smith ZOO- 84 BERNARD A. GILHEANY, Primary Examiner.

H. A. LEWITTER, Assistant Examiner. 

1. IN AN ALARM FOR SWIMMING POOLS, A FLOAT COMPRISING A SUBSTANTIALLY CYLINDRICAL BODY HAVING A CENTRAL AXIS AND A RADIUS, SAID BODY HAVING AN UPPER SURFACE PROVIDING AT LEAST ONE SURFACE MEANS SLOPING FROM SAID AXIS TOWARD THE PERIPHERY OF SAID BODY ADAPTED TO SUPPORT AN ALARM ACTUATED SWITCH MEANS, A LOWER SURFACE, SAID LOWER SURFACE INCLUDING MEANS FOR ENTRAPPING AIR BENEATH SAID FLOAT, SAID LAST MENTIONED MEANS INCLUDING SYMMETRICALLY DOWNWARDLY EXTENDING PORTIONS FORMING A SERIES OF OPEN CUT-OUT AREAS. 